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A267296
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Circulant Ramsey numbers RC_1(3,n) of the first kind.
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1
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3, 3, 9, 14, 15, 22, 25, 34, 37, 46, 49
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OFFSET
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2,1
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COMMENTS
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The smallest positive number a(n), such that any triangle-free cyclic (also known as circulant) graph with a(n) vertices has independence number at least n. The terminology and the terms given here are from Harborth and Krause.
Moreover, the sequence is related to the ordinary two-color Ramsey numbers R(3,n), given in A000791, by the relation a(n) <= A000791(n) for all n, as proved by Kalbfleisch. This inequality is known to be an equality for n = 2 or 4 <= n <= 5.
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REFERENCES
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H. Harborth, S. Krause, Ramsey Numbers for Circulant Colorings, Congressus Numerantium 161 (2003), 139-150.
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LINKS
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CROSSREFS
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KEYWORD
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nonn,hard,more
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AUTHOR
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STATUS
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approved
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